The use of medicinal plants as source of health remedies in malaria endemic regions has significantly increased as a result of increase malaria parasite resistant to some synthetic drugs currently in used. Extracts prepared from Piliostigma thonningii and Lophira lanceolata leaves are used for curing malaria and other related human diseases in Nigeria. The aim of this study was to investigate the possible haematotoxicity and histotoxicity profile of P. thonnigii and L. lanceolata in Wistar albino rats. Graded doses of Ethanolic extracts prepared from P. thonningii and L. lanceolata leaves were administered day-to-day (1000, 1500 and 2000 mg/kg) orally to rats for 14 days respectively and the effects on body weight, relative organ weight, haematology, serum biochemical and histopathology parameters were evaluated. The relative weights of the sampled organs of treated rats were unaffected. No significant deviations in haematological profile of treated animals. Both extracts elicited significant decline in BUN levels at 1000 mg/kg dose. Histopathological findings reveal evidence of some mild and focal lesions. This study indicates that P. thonnigii and L. lanceolata leaves ethanolic extracts have no obvious negative effects when applied orally under a controlled dosage of 2000mg/ kg body weight. However, the histopathological studies therefore calls for watchfulness or caution to constant/repeated exposure to the extracts.

Keywords : Piliostigma thonningii, Lophira lanceolata, haematotoxicity, histotoxicity, Wistar albino rats.